Data processing systems and data processors are used in myriad applications which in turn have an impact on virtually every aspect of life. The utility of these myriad applications can ordinarily be enhanced by improving the operational flexibility of the associated data processing systems and data processors.
Conventional data processing systems utilize registers for a variety of purposes, as is well known in the art. Conventionally, each register bit is either a read/write bit whose logic value can be selectively written over and thus changed, or a hard-wired bit whose logic value is fixed during manufacturing and cannot be changed later. The aforementioned absolute unchangeability of hard-wired register bits can be disadvantageous from emulation and testability standpoints.
It is therefore desirable to provide for the use of hard-wired register bits which do not have the aforementioned disadvantageous characteristic of absolute unchangeability.
The present invention provides the capability of selectively configuring a register bit as a hard-wired bit or a read/write bit.